1. Field Of Invention
This invention relates to improving blocking circuit performance in a power line communication system.
2. Description Of Related Art
Conventional power line signal receivers block noise generated by devices connected to the power supply lines of a house by using a blocking circuit. Such blocking circuits reduce noise voltages generated by devices such as home appliances from interfering with signal receivers receiving signals through the power lines.
Because power lines connected to houses have three lines where the voltage between a positive power line and a negative power line is about 240 volts, home appliances that require only 120 volts are connected between one of the positive and negative power lines and a neutral line. Thus, noise voltages are generated across the positive and negative power lines independently causing a net difference voltage between the positive and negative power lines.
The above noise voltage across the positive and negative power lines are only partially removed by the blocking circuit. Thus, there is a need to improve the blocking circuit performance for further reducing the noise induced onto power lines by devices such as home appliances.